VMware Workstation 5.5

Using Two-Way Virtual Symmetric Multiprocessing (Experimental)

For all supported configurations of 32-bit and 64-bit host and guest operating systems running on multiprocessor host machines, Workstation versions 5.5 and later provide experimental support for two-way virtual Symmetric Multiprocessing (Virtual SMP). This enables you to assign two virtual processors to a virtual machine on any host machine that has at least two logical processors.

Note: The following are all considered to have two logical processors:

A single-processor host with hyperthreading enabled

A single-processor host with a dual-core CPU

A multiprocessor host with two CPUs, neither of which are dual-core or have hyperthreading enabled

Note: On hyperthreaded uniprocessor hosts, performance of virtual machines with Virtual SMP may be subpar.

Guests with more than two virtual processors are not supported in Workstation. However, you can power on and run multiple dual-processor virtual machines concurrently.

You can set the number of processors for the virtual machine in the virtual machine settings editor (VM > Settings), in the Hardware tab under Processors. The number of virtual processors is also displayed in the summary view of the virtual machine. You can also set the number of virtual processors when you create a virtual machine in the New Virtual Machine Wizard. This setting is available only if you choose to create a custom configuration; it does not appear in the typical configuration.

If the host is a uniprocessor machine and is not hyperthreaded, assigning two processors is neither supported nor recommended: a warning message will appear. You can disregard this message and assign two processors to the virtual machine, but, once you have finished creating the virtual machine, you will not be able to power it on unless you move it to a host machine with at least two logical processors.

Virtual machines with SMP are supported only for Workstation versions 5.5 and later. A virtual machine created in Workstation version 5.5 with two virtual processors cannot be powered on or resumed in Workstation versions 5.0 and earlier. Also, if you suspend an SMP guest in Workstation 5.5, you cannot resume the virtual machine in Workstation versions 5.0 and earlier.

Moving SMP Virtual Machines between Workstation and ESX Server

You can use Workstation 5.5 or later, running on a multiprocessor host machine, to open a virtual machine, created in VMware ESX Server, that has one or more virtual processors. However, in Workstation you cannot power on or resume a virtual machine that has more than two virtual processors assigned, even if more processors were assigned when the virtual machine was created in ESX Server.

If you use Workstation to open a virtual machine that has more than two virtual processors assigned, the virtual machine's summary view and the virtual machine settings editor (VM > Settings) will display the number of processors as Other (x), where x is the number of processors originally assigned in ESX Server. Workstation preserves this original configuration setting for the number of processors, even though two is the maximum number of processors supported. You must change this setting to two processors before you can power on the virtual machine in Workstation. Note that once you commit a change to this setting, by clicking OK in VM > Settings, the original setting for number of processors is discarded, and no longer appears as an option in VM > Settings.